762
FXUS62 KJAX 311230
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
830 AM EDT Sun Aug 31 2025

...New UPDATE...

.UPDATE...
Issued at 821 AM EDT Sun Aug 31 2025

For the latest NE FL and SE GA Daily Key Messages please visit:
https://www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf

Forecast on track for increasing Northeast winds with heavy
rainfall threat along the Atlantic Coastal areas, mainly along the
NE FL coast and areas from I-95 east towards the beaches.
Northeast wind surge as high pressure builds down the SE US
coastline will push sustained winds into the 15-25 mph with wind
gusts of 30-35 mph at times, strongest for beachfront locations as
this wind surge along the SE GA coast this morning moves down the
NE FL coast this afternoon. Some of the blended model guidance is
suggesting peak wind gusts around 40 mph along the Atlantic Coast,
but not enough confidence for a Wind Advisory at this time. Temps
will remain below normal with the cloud cover and rainfall along
the Atlantic Coast with highs only around 80F, while further
inland expect enough breaks in the clouds for temps to reach into
the middle 80s.

&&

.SYNOPSIS...
Issued at 450 AM EDT Sun Aug 31 2025

Early morning surface analysis depicts weak low pressure (1011
millibars) situated over the Gulf Stream waters adjacent to
northeast FL, with coastal troughing beginning to sharpen over our
near shore Atlantic waters. The low pressure center was located
along a nearly stationary frontal boundary that stretches across
north central FL and extends westward just to the south of the
northern Gulf coast. Meanwhile, strengthening high pressure (1026
millibars) was building eastward from the Great Lakes region to
New England and the Mid-Atlantic states. Aloft...deep troughing
prevails over the eastern third of the nation, with ridging
building from Texas and the Four Corners region northward through
the Plains states. Latest GOES-East derived Total Precipitable
Water imagery indicates that a much drier air mass was filtering
over locations along and north of Interstate 10, where PWATS have
fallen below 1.5 inches for locations north of Waycross and 1.6 -
1.75 inches elsewhere. Deeper moisture has been shunted
southeastward to north central and coastal northeast FL, where
PWATS remain mostly in the 1.8 - 2 inch range. Low pressure
offshore was allowing for lower stratus clouds and a few light
showers to pinwheel along our Atlantic coastal communities, with
low and mid level stratocumulus clouds expanding in coverage
elsewhere. A convergent band of heavier downpours was setting up
over the offshore waters adjacent to northeast FL, with this
activity moving slowly southward. Otherwise, temperatures and
dewpoints at 09Z have fallen to the mid and upper 60s for inland
portions of southeast GA and northern portions of the Suwannee
Valley, with mostly lower 70s elsewhere.

&&

.NEAR TERM...
(Today and Tonight)
Issued at 450 AM EDT Sun Aug 31 2025

Our local pressure gradient will tighten from north to south today
as strong high pressure stretching from the Great Lakes states
eastward to New England will wedge down the southeastern seaboard.
This feature will gradually push a broad, weak low pressure
center located off the southeast GA coast southward in tandem with
a frontal boundary that has been stuck over our region.
Strengthening low level northeasterly flow will increase
convergence along the southeast GA and northeast FL coasts during
the predawn and early morning hours, with a tight moisture
gradient in place along the I-95 corridor allowing for slow moving
covergent bands of showers to increase in coverage and intensity
early this morning. Meanwhile, a drier air mass will continue to
filter into inland portions of southeast GA as well as northern
portions of the Suwannee Valley today, allowing for breaks in the
late morning cloud cover that will allow temperatures to warm back
into the 80s for the first time in 3 days.

Heavy showers and a few embedded thunderstorms will slowly shift
southward as the day progresses, with the drier air mass likely
limiting coverage to scattered by this afternoon for coastal
southeast GA. Locally heavy rainfall will be possible along
the I-95 corridor in northeast FL through this afternoon, with
amounts around 1 inch at most locations by later this evening,
with localized totals of 2-3 inches possible at coastal locations.
Breezy north-northeasterly winds and stubborn low level stratus
and marine stratocumulus should keep highs in the low to mid 80s
at coastal locations today.

A tight local pressure gradient will persist tonight, with the
best coastal convergence remaining along the northeast FL coast,
with persistent bands of locally heavy downpours potentially
shifting inland across Clay and Putnam Counties as well. Breezy
onshore winds will keep lows in the mid 70s along the northeast FL
coast and the lower 70s for coastal southeast GA. Meanwhile, the
drier air mass and clearing skies overnight will again allow lows
to fall to the mid and upper 60s for inland southeast GA and
northern portions of the Suwannee Valley.

&&

.SHORT TERM...
(Monday through Tuesday night)
Issued at 450 AM EDT Sun Aug 31 2025

The frontal boundary from the past weekend will continue to push
south of the local area towards central FL as drier air continues
to move into the area. This will limit precipitation chances for
much of the interior locations of SE GA and NE FL. Onshore NE flow
will become established as coastal troughing develops, allowing
for gusty conditions along the coast. Scattered to numerous
showers/storms will move in from the Atlantic towards coastal
locations, with higher chances over coastal NE FL. WPC has
highlighted coastal NE FL and north central FL counties for a
Marginal Risk of Excessive Rainfall on Monday, with the Marginal
Risk Excessive Rainfall only expected along the north central FL
counties on Tuesday as the frontal boundary begins to shift.

&&

.LONG TERM...
(Wednesday through Saturday)
Issued at 450 AM EDT Sun Aug 31 2025

By midweek, the frontal boundary over central FL will continue to
shift northward as a weak surface low develops along the eastern
sea board. The lifting boundary will allow for shower and storm
coverage to increase from south to north across on Wednesday. By
the later part of the upcoming week, drier conditions will once
again begin to build into the local area as the front and low
moves further towards the NE and the arrival of a dry cold front
from the NW will see precipitation chances begin to trend downward
once again.

&&

.AVIATION...
(12Z TAFS)
Issued at 714 AM EDT Sun Aug 31 2025

LIFR CIGS at SSI/GNV/JAX/CRG/VQQ this morning will expand to SGJ
as the NE wind surge pushes down the Atlantic Coast with best
rainfall chances at the coastal TAF sites, while should be able to
cover inland locations with VCSH. The increase in winds to 10-15
knots with gusts to 20-25 knots will slowly lift CIGS back into
MVFR levels through the afternoon hours. NE winds remain gusty at
the coastal TAF sites with rainfall chances through tonight,
while a lowering of CIGS back to IFR levels at GNV/VQQ/JAX
expected later tonight time frame.

&&

.MARINE...
Issued at 450 AM EDT Sun Aug 31 2025

Low pressure located over the Gulf Stream waters adjacent to the
GA coast will shift slowly southward across the offshore waters
adjacent to northeast FL in tandem with a frontal boundary.
Meanwhile, strengthening high pressure extending from the Great
Lakes eastward across New England will wedge down the southeastern
seaboard, sending a surge of northeasterly winds and building seas
across our local waters from north to south today. Small Craft
Advisory conditions will overspread the waters north of St.
Augustine this afternoon as speeds increase to around 20 knots,
with Caution conditions of 15-20 knots reach the waters south of
St. Augustine later today. Seas will build to the 3-5 foot range
across the waters north of St. Augustine this afternoon, with 2-4
foot seas for the waters south of St. Augustine. Seas will then
build to Caution levels of 4-6 feet north of St. Augustine tonight
and 3-5 feet for the waters south of St. Augustine. Seas will
then peak on Monday and Monday night, with 5-7 foot seas for the
waters north of St. Augustine, while seas reach Caution levels of
4-6 feet south of St. Augustine.

Waves of showers and embedded thunderstorms will impact our local
waters through midweek. Northeasterly winds will begin to
gradually weaken by late Tuesday and Wednesday, allowing for seas
to gradually subside. Coverage of showers and thunderstorms will
then decrease later this week as prevailing winds shift to
westerly ahead of a series of approaching cold fronts.

Rip Currents: Strengthening onshore winds from north to south
across our region today will create a high risk of rip currents as
breakers build to the 2-4 foot range this afternoon. Northeasterly
winds will become windy on Monday, with breakers building further
to the 3-5 foot range, keeping a high risk in place at all area
beaches. Persistent onshore winds and only slowly subsiding surf
conditions, with breakers generally remaining in the 2-4 foot
range, will likely keep a high risk in place at all area beaches
through midweek.

&&

.HYDROLOGY...
Issued at 450 AM EDT Sun Aug 31 2025

Heavy rainfall potential will mainly remained confined along the
I-95 corridor and Atlantic Coastal Counties through midweek, with
additional rainfall totals of 1-3 inches expected, with locally
higher amounts possible. The Weather Prediction Center (WPC) has
maintained "Marginal" Risks (level 1 of 4) for these areas through
midweek, highlighting the risk for mainly localized flooding. Lower
total amounts expected over inland northeast and north central
FL, but with daytime heating, any of the isolated thunderstorm
activity will still have heavy rainfall potential. However, the
main threat will still be along the Atlantic Coastal areas, where
narrow convergent rain bands set up in the strong onshore wind
pattern that develops later today, with downpours potentially
"training" or repeatedly impacting the same locations within some
of these rain bands.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  85  66  84  63 /  40  20  10   0
SSI  83  73  83  73 /  40  30  40  20
JAX  84  72  84  71 /  50  40  60  20
SGJ  85  75  85  74 /  70  60  70  30
GNV  87  71  86  69 /  50  30  50  10
OCF  87  71  86  72 /  70  40  60  10

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk through late Monday night for FLZ124-125-
     138-233-333.

GA...High Rip Current Risk through late Monday night for GAZ154-166.

AM...Small Craft Advisory until 11 PM EDT Monday for AMZ450-470.

     Small Craft Advisory from noon today to 11 PM EDT Monday for
     AMZ452-472.

     Small Craft Advisory from 4 PM this afternoon to 11 PM EDT
     Monday for AMZ454-474.

&&

$$